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Full Discussion: Help with simple program. (beginner)
Top Forums Shell Programming and Scripting Help with simple program. (beginner) Post 302513964 by Corona688 on Thursday 14th of April 2011 12:04:35 PM
Old 04-14-2011
A good start but there's a few things to figure out here:
Code:
if [ $ cat /etc/passwd | cut -d: -f1= "$username" ]

You don't put programs inside [ ] like that, you can just put them there raw.

That is also a useless use of cat, whenever you have cat stuff | program it's better to do program < stuff.

There's a trick you can do with grep to check for a user in the password file:

Code:
if grep -q "^${username}:" /etc/passwd
then
...

The ^ makes it look at the beginning of the line, so it looks for ${username}: at the beginning of any line in /etc/passwd. The -q tells it not to print anything, just return true or false as usual.

Code:
while [ $(who | grep $username) != 0 ]

This is a useless use of backticks (since the $(stuff) syntax is a special form of backticks). You don't check a return value in that fashion, either -- what that statement would actually end up doing is checking the string output of who | grep $username.

How you check a return value is like:

Code:
# there really are 'true' and 'false' programs, so go ahead and
# try these statements
if true
then
       echo "true returns true"
fi

if ! false
then
        echo "false returns false"
fi

So how about:
Code:
while who | grep -q "${username}"
do
...

Code:
exit 1

1 means error, by returning 1 you're telling whatever ran it that your program failed. Use 'exit 0' to show that your program ran successfully.
 

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LEARN ABOUT SUNOS

list-file-groups

asadmin-list-file-groups(1AS)					   User Commands				     asadmin-list-file-groups(1AS)

NAME

       asadmin-list-file-groups, list-file-groups - lists the file groups

SYNOPSIS

       list-file-groups  --user  admin_user  [--password  admin_password] [--host localhost] [--port 4848] [--secure|-s] [--passwordfile filename]
       [--terse=false] [--echo=false] [--interactive=true] [--authrealmname auth_realm_name] [--name username]

       Lists the available groups in the file user. If the name option is not specified, then all groups are listed.

       This command is supported in remote mode only.

OPTIONS

       --user		       authorized domain application server administrative username.

       --password	       password to administer the domain application server.

       --host		       machine name where the domain application server is running.

       --port		       port number of the domain application server listening for administration requests.

       --secure 	       if true, uses SSL/TLS to communicate with the domain application server.

       --passwordfile	       file containing the domain application server password.

       --terse		       indicates that any output data must be very concise, typically avoiding human-friendly sentences and favoring well-
			       formatted data for consumption by a script. Default is false.

       --echo		       setting to true will echo the command line statement on the standard output. Default is false.

       --interactive	       if set to true (default), only the required password options are prompted.

       --authrealmname	       filename where you have different stores for file auth realm.

       --name		       name of the file user.

       Example 1: Using the list-file-groups command

       asadmin> list-file-groups --user admin1 --password adminadmin1
       --host pigeon --port 5001 --name sample_user
       Command list-file-groups executed successfully

EXIT STATUS

       0		       command executed successfully

       1		       error in executing the command

       asadmin-delete-file-user(1AS), asadmin-update-file-user(1AS), asadmin-create-file-user(1AS), asadmin-list-file-users(1AS)

J2EE 1.4 SDK							    March 2004					     asadmin-list-file-groups(1AS)
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